Well, 1978 was a good year, the last year for that series, and by then they have gotten the gremlins out

The 1592cc engine is much maligned, but I think there is nothing wrong with it in itself. Some say it can be bored out to 84mm, so it cam become an 1756cc engine. Others say it's too much of an overbore. I've never tried, so I can't say for sure, but it would be one way to bring the car back to the original specs.